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Guest EVL-R33

hey ppl, recently when changin to 4th gear from high revs from either 2nd or 3rd my 4th gear keeps crunching for no reason i know its something wrong but i just wanna see if anyone would know the problem or experience it b4,

At the start it would crunch really hard and not go in, now after 2 weeks it goes in but still crunchs softly, it needs fixing a.s.a.p i just got back from my holiday and its time to get it done...

thank you..

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Mine does it on 4th as well. I just figured the synchro was on it's way out and am living with it. If you're just cruising then try and match the revs to the gear when you're changing up into 4th. If you don't know what i mean, try pulling the shifter 'against' the gate into 4th when you change up with your foot on the clutch instead of just forcing it in. You'll find that as the revs of the engine match the revs of the flywheel, it will just go in by itself.

I don't know if this makes any sense at all but I hope it helps. It's just like riding a motorbike. I hardly ever use the clutch on up-changes. All I do is put a little bit of pressure on the shifter with my toe and back off the revs slightly so it clicks into gear.

Good Luck

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There was a similar thread a while back on SDU i think and from memory they suggested a good oil change with a stick of Nulon GE70 (i think that's what it was), drive nicely for 500kms then see if it still crunches when giving it a bit of welly.

I haven't tried this so dunno if it makes a difference.

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The shockproof oils will definately help, they should lessen any additional strain on the synchros and reduce the crunching noise. It is not however going to fix the problem, therefore I think that saving up to replace the synchro might be a good idea. At the same time get them to check the whole box, if one synchro is going then the box may be on it's way out.

See'ya :burnout:

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The problem with the syncro's is sometimes an issue with the oil being too slippery and not slowing the shaft down before changing.

Nissan did an upgrade to the GTR boxes which had the same problem but cost about 2K for parts alone.

I have solved the problem on 3 x Nissan boxes so far for about $100-$120 by using Redline Lightweight Shockproof oil ( blue smurf ).

Is amazing stuff and ask Micko who will vouch how well it is still going.

Ken

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  • 3 weeks later...

I got it from CRD in silverwater. Bloody expensive @ about $100, but cheaper than pulling out the gearbox and reconditioning it :;

I don't think its a permanent fix, the gearbox still baulks at a quick change, but the crunching is gone and the motion is smoother. Thumbs up from me.

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Originally posted by benm

Dumb question but where and how do u replace gearbox oil ? Anyone got any pics of exactly where it goes ?

On the bottom ot the box there's a plug, undo that to drain then plug back up. On the drivers side of the box, there's another plug. Open and fill up until it starts pouring out a little.

Duncan, you bum!:)

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